Book of Treasure is a time-limited event consisting of several steps. Each step has its own book (red-colored match item), goal, and reward.
You collect books by clearing them while playing a level. The books you collect in a level are added to your score.
When you reach the book goal of a step, you get a reward and move on to the next step.
When you complete all steps in the event, you win the Grand Prize.
You win extra books from Hard and Super Hard levels.
The more steps you complete, the more rewards you win.